Data Sheet for Product

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Siemens Climatix Extension Modules ECV2 CB1N3944en
Smart Infrastructure 2021-02-16
Electronic expansion valves control refrigerant mass flow in evaporators in
evaporators for chillers, air-conditioners and refrigerators applications. In addition
modulating valves can be used for several control functions such as liquid injection,
hot gas bypass and evaporator pressure regulation.
ECV2 extension modules are designed as an electronic expansion valves driver,
featuring two independently channel drive bipolar stepper motors. With the main
controller one ECV2 module independently can manage two electronic expansion
valves. Each channel of ECV2 module controls refrigerant superheat and optimizes
the efficiency of the refrigerant circuit, to enhance the maximum capacity for
chillers, air-conditioners and refrigerators.
Modulating refrigerant valves that are equipped with bipolar stepper motors are
available for a wide capacity range.
Bipolar permanent magnet and hybrid motors are constructed with exactly the
same mechanism as is used on unipolar motors, but the two windings are wired
more simply, with no center taps. Thus, the motor itself is simpler but the drive
circuitry needed to reverse the polarity of each pair of motor poles is more
complex.
Bipolar permanent magnet and hybrid motors have two windings. The drive
circuitry for such a motor requires an H-bridge control circuit for each winding.
Briefly, an H-bridge allows the polarity of the power applied to each end of each
winding to be controlled independently.
Electronic expansion
v
alve
Bipolar stepper motors